FORMATION OF POLYIMIDE RESIN FILM PATTERN

PURPOSE:To prevent the cracking of polyimide resin films, the deformation in pattern edges, and the production of scum, and shorten etching time by etching polyimide resin films in alkali using a negative resist film as a mask, subjecting the resist film to heat treatment at a specified temperature, and thereafter stripping the film. CONSTITUTION:Part of the wiring layer 2 formed on a semiconductor substrate 1 is uncovered with an insulating layer film 3 to form an electrode 8. Polyamide acid solution is applied to the semiconductor substrate, which is then subjected to heat treatment to form a polyimide resin film 4. A negative resist film 5 is formed thereon. The resist film 5 is exposed through a photomask 6, and developed to form a pattern 7. Subsequently, alkali etching is performed to bare bonding pads 8 in the pattern 7. Heat treatment is conducted at a temperature of 140-220 deg.C to strip the negative resist film 5. This prevents the dissolution and cracking of the surface of polyimide resin films.